The consortium of Acciona and YIT has been chosen as the preferred bidder for an undersea heat recovery project for Helsinki by Finnish energy company Helen.
The contents of this design and build contract with €400m (US$481m) value will be constructed in a 17km subsea tunnel using a TBM, which is the third-longest of its kind in the world. Capturing seawater at a temperature of 2 deg Celsius and a depth of almost 70m in the Baltic Sea, this tunnel will transfer the water at 50m3/second to Helen’s plant in Salmisaari for use in the capital’s district heating system.
Working on the underground chambers to house the facilities, a 9km drill, and blast tunnel to return excess water to the sea, as well as the water intake caisson and piping, are also other subsets of this contract.
The estimated date for completing the development phase is autumn 2024, while construction is scheduled to take about five years.
Although YIT considers as Finland’s largest construction company, the project is Acciona’s first in Finland.